Sustainable Energy

Cooling Down in Motown

New superconducting cables are put to the test in Detroit.

A gritty section of Detroit surrounds one of the city’s oldest electric power stations. But the technology that Detroit Edison is installing at the Frisbie substation is pure 21st century-underground superconducting cables that can transmit immense currents of electricity with near perfect efficiency.

While increasing energy demands are putting more and more stress on the nation’s long-distance power transmission network, cities are suffering their own version of electric gridlock; in many locations, underground transmission lines are fast reaching capacity and are literally burning up. Superconducting cables, like the ones being installed in Detroit, could safely triple the power moving through existing conduits, avoiding the need to dig up the streets-even making room for fiber-optic communications lines.

The Frisbie demonstration marks a milestone in electricity know-how-one of the first commercial applications of high-temperature superconductors. These ceramics, first fashioned by IBM researchers in 1986, now transmit alternating currents with nearly zero resistance at temperatures as high as -139 C (the
materials can be cheaply cooled to that temperature using liquid nitrogen). In contrast, conventional copper cables dissipate as much as 10 percent of the power they carry because of resistance; that lost power escapes as heat, which limits just how much juice can flow before the cable melts.

This story is part of our July/August 2001 Issue
See the rest of the issue
Subscribe

American Superconductor, the firm making the materials being tested in Detroit, has been trying to find real-life uses for the ceramics since it was founded in 1987 by MIT materials scientists Greg Yurek and John Vander Sande. Their trick is to fabricate the superconductor as flexible conductive tapes. Pirelli Cables and Systems, the world’s largest producer of power cables, wraps the tape with insulation and a protective sheath on the outside and a channel up the middle for the liquid-nitrogen coolant, which keeps the tape in superconducting mode.

Surrounded by shuttered buildings and empty lots, the Frisbie station has plenty of spare capacity-meaning its 13,500 customers won’t be left in the dark if the superconducting cables fail. But Detroit Edison is already looking at using the technology to replace overloaded conventional cables serving busier sections of the city.

And Pirelli R&D manager for superconductivity Marco Nassi says success in Detroit should lead to commercialization of superconducting cables elsewhere “within the next few years.” Because the superconducting materials still must be cooled down to liquid-nitrogen temperatures, applications are likely to be limited to relatively short-range trans-mission in underground cables, rather than long-distance transmission. But that could still be a savior for a number of cities whose maxed-out underground transmission systems are literally burning up.

Become an MIT Technology Review Insider for in-depth analysis and unparalleled perspective.

Subscribe today

Uh oh–you've read all of your free articles for this month.

Insider Premium
$179.95/yr US PRICE

More from Sustainable Energy

Can we sustainably provide food, water, and energy to a growing population during a climate crisis?

Want more award-winning journalism? Subscribe to Insider Plus.
  • Insider Plus {! insider.prices.plus !}*

    {! insider.display.menuOptionsLabel !}

    Everything included in Insider Basic, plus ad-free web experience, select discounts to partner offerings and MIT Technology Review events

    See details+

    What's Included

    Bimonthly home delivery and unlimited 24/7 access to MIT Technology Review’s website.

    The Download. Our daily newsletter of what's important in technology and innovation.

    Access to the Magazine archive. Over 24,000 articles going back to 1899 at your fingertips.

    Special Discounts to select partner offerings

    Discount to MIT Technology Review events

    Ad-free web experience

/
You've read all of your free articles this month. This is your last free article this month. You've read of free articles this month. or  for unlimited online access.